MJ Duncan & Sons is a firmly established building contractor serving the Leinster area. Based in Co. Dublin we are dedicated to delivering a high quality building, construction and maintenance service to the domestic, commercial and industrial sectors.

MJ Duncan & Sons undertake a range of works such as protected structures using traditional building methods, extensions, refurbishment works and general maintenance duties.

We have built on a good reputation with our clients and have had the pleasure in working with many established architects and clients such as the ones shown to the right of this page.

Much of our work comes by referral from previous customers. We are committed to offering a first class service aimed at satisfying our customer needs.

For more information on any of our services please do not hesitate to call us on 01 621 7856 / 01 621 7857.


  • Irish Rail
  • Barclays
  • Dublin City Council
  • South Dublin County Council
  • Stewarts Hospital
  • Franciscans
  • OPW
  • HSE
  • Brazil Associates
  • Aughey O'Flaherty
  • Coady Partnership Architects
  • Node Architects
  • Howley Hayes Architects
  • Crean Salley Architects
  • James Ahern Architects
  • Dublin Bus
  • Dublin & Dun Laoghaire Education & Training Board
  • Law Society of Ireland
  • The Dominicans